Systems and apparatus for gait modulation and methods of use

ABSTRACT

An apparatus includes a frame, a sensor, and an electric stimulator. The frame is removably couplable to a portion of a limb. The sensor is configured to produce a first signal associated with a gait characteristic at a first time, and a second signal associated with the gait characteristic at a second time, after the first time. The electric stimulator is removably coupled to the frame and is in electrical communication with an electrode assembly and the sensor to receive the first signal substantially at the first time and the second signal substantially at the second time. Based in part on the gait characteristic at the first time, the electric stimulator sends a third signal to the electrode assembly to provide an electric stimulation to a portion of a neuromuscular system of the limb substantially during a time period defined between the first time and the second time.

BACKGROUND

The embodiments described herein relate generally to gait modulationsystems, and more particularly, to a functional electrical stimulation(FES) orthosis for gait modulation and methods of using the same.

It is known that pathologies of the neuromuscular system due to diseaseor trauma to the central nervous system, such as for example, stroke,spinal cord injury, head injury, cerebral palsy, and multiple sclerosiscan impede limb function of the arms or legs (or portions thereof).Gait, the biomechanical description of walking, can suffer static anddynamic parameter variations due to neuromuscular impairments, whichcause non-symmetrical walking, reduced walking speed, and reducedwalking stability. For example, drop foot describes a gait attributableto weak or uncoordinated activation of the ankle dorsiflexors due todisease or trauma to the central nervous system. Patients suffering fromdrop foot tend to drag the foot during the swing phase of walking andusually try to compensate for this dragging by hiking the correspondinghip or swinging the corresponding leg in a circular motion. Thesepatients tend to have reduced stability, are prone to frequent falls,and their walking movements are unaesthetic and energy consuming.

Limb muscles, however, can generally be activated with functionalelectrical stimulation (FES). In FES, precisely timed bursts of shortelectrical pulses (e.g., from a neuroprosthetic, an FES orthosis, and/orthe like) are applied to motor nerves to generate muscle contraction,which can be applied to enhancing limb function. Althoughneuroprosthetic systems are known, some such systems suffer fromdrawbacks that prevent the systems from being widely used by potentialpatients. For example, in instances in which stroke or brain injuryresults in problems with arm movement or gait, such problems are oftenaccompanied by hand impairment on the same side of the body as theproblematic limb. Thus, donning an FES orthosis is often carried outusing solely the contra-lateral, unaffected hand. Moreover, the postureof the plegic limb is often problematic, especially in cases wherespasticity results in reduced voluntary movements and/or limited passiverange of motion of the limb joints. Consequently, objectivebiomechanical problems exist in donning some known orthotic devices aswell as locating the electrodes in exact positions onto the limb, whichis essential for activating the desired movement pattern. As such, someknown neuroprosthetic devices fail to enable facile, quick, and accuratedonning of the device by an impaired patient using a single hand, andparticularly, when the least effected hand is shaky or otherwiseunstable.

FES devices typically utilize a stimulator unit to create and controlthe electrical pulses being applied to motor nerves that is physicallyseparate from the FES orthosis. The external stimulator unit, which isconnected to the FES orthosis by several electrical wires, is located onthe body of the user and/or is otherwise worn by the user. These devicescan be inconvenient for the user. Specifically, the wiring, which isusually arranged to run along the leg under the clothing to connect thedevice components, can be difficult to operate, cumbersome anduncomfortable.

In other instances, an FES orthosis can be a self-contained device. Forexample, some known orthoses can include a stimulator unit coupled to anarrow band that is made of a thermoplastic material, which is molded tothe limb anatomy of an individual user by heating and softening thethermoplastic material and subsequently fitting the band to the contourof the underlying limb segment. Thus, the shape and size of the deviceand the electrode positioning is custom-fitted to the leg of one userand individualized for the user. This procedure is carried out by amedical professional trained, for example, to accurately identify thestimulation points that cause contraction of the muscles, positioningand locking the electrodes thereto.

Activation of the leg muscles by electrical stimulation typicallyincludes transferring high stimulation currents through one or moreelectrodes to the skin surface of the patient, which activates skinsensory receptors in addition to underlying excitable motor nerve andmuscle tissue. As a result, the intensity of sensory activation oftendepends on the intensity of the current density passing through the skinsurface. The level of muscle activation, therefore, is often limited tothe patient's individual tolerance to activation of such skin painsensors. Thus, the stimulation parameters of the device are adjusted foreach patient, which can be time consuming and often includes attachingthe orthosis to a control device via wires.

Therefore, a need exists for improved systems and apparatus for aneuroprosthetic system that can be easily and accurately donned on thelimb by patient and that includes a stimulation unit that can beremotely controlled and/or adjusted.

SUMMARY

Systems and apparatus for gait modulation and methods of use aredescribed herein. In some embodiments, an apparatus includes a frameassembly, a sensor, and an electric stimulator. The frame is configuredto be removably coupled to a portion of a limb such that the portion ofthe limb is substantially enveloped by the frame. The sensor is operablycoupled to the frame and is configured to produce a first signalassociated with a gait characteristic at a first time, and a secondsignal associated with the gait characteristic at a second time, afterthe first time. The first time and the second time define a time periodtherebetween. The electric stimulator is removably coupled to the frameand is in electrical communication with the sensor and an electrodeassembly. The electrode assembly is in electrical communication with aportion of a neuromuscular system of the limb when the frame is coupledthereto and is configured to receive the first signal from the sensorsubstantially at the first time and the second signal from the sensorsubstantially at the second time. Based at least in part on the gaitcharacteristic at the first time, the electric stimulator is configuredto send a third signal to the electrode assembly substantially at thefirst time operable to cause the electrode assembly to provide anelectric stimulation to the portion of the neuromuscular system of thelimb substantially during the time period.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic illustration of a system for gait modulationaccording to an embodiment.

FIG. 2 is a perspective view of a functional electrical stimulation(FES) orthosis for gait modulation according to an embodiment.

FIG. 3 is a perspective view of a portion of the FES orthosis of FIG. 2illustrating a coupling an electric stimulator to a frame.

FIG. 4 illustrates a portion of a patient donning of the FES orthosis ofFIG. 2 on an impaired leg.

FIG. 5 is a schematic side view of a portion of the FES orthosis of FIG.2 illustrating an electrical connection between the electric stimulatorof FIG. 3 and an electrode assembly.

FIG. 6 is a rear perspective view of the FES orthosis of FIG. 2illustrating the electrode assembly of FIG. 5 coupled to an innersurface of the frame of FIGS. 3-5.

FIG. 7 is a schematic block diagram illustrating an electrical system ofthe FES orthosis of FIG. 2.

FIG. 8 illustrates the FES orthosis of FIG. 2 included in a system forgait modulation.

FIG. 9 is a flowchart illustrating a method of using an FES orthosis forgait modulation according to an embodiment.

FIG. 10 is a flowchart illustrating a method of using an FES system forgait modulation according to an embodiment.

DETAILED DESCRIPTION

The embodiments and methods described herein relate to an improvedfunctional electrical stimulation (FES) orthosis for users sufferingfrom gait problems such as drop foot. The orthosis can easily be donnedon the leg, even by patients suffering from impairments that mightotherwise hinder the donning of the orthosis. In some embodiments, anapparatus includes a frame assembly, a sensor, and an electricstimulator. The frame is configured to be removably coupled to a portionof a limb such that the portion of the limb is substantially envelopedby the frame. The sensor is operably coupled to the frame and isconfigured to produce at least a first signal associated with a gaitcharacteristic at a first time, and a second signal associated with thegait characteristic at a second time, after the first time. The firsttime and the second time define a time period therebetween. The electricstimulator is removably coupled to the frame and is in electricalcommunication with the sensor and an electrode assembly. The electrodeassembly is in electrical communication with a portion of aneuromuscular system of the limb when the frame is coupled thereto andis configured to receive the first signal from the sensor substantiallyat the first time and the second signal from the sensor substantially atthe second time. Based at least in part on the gait characteristic atthe first time, the electric stimulator is configured to send a thirdsignal to the electrode assembly substantially at the first timeoperable to cause the electrode assembly to provide an electricstimulation to the portion of the neuromuscular system of the limbsubstantially during the time period.

In some embodiments, a method includes receiving, at an electricstimulator and from a sensor, a first signal associated with a gaitcharacteristic. Based at least in part on the first signal associatedwith the gait characteristic, one or more system parameters iscalculated. A signal is sent, based at least in part on the one or moresystem parameters, from the electric stimulator to an electrode assemblyto cause the electrode assembly to provide an electric stimulation to aportion of a neuromuscular system of a limb. A second signal associatedwith the gait characteristic is received at the electric stimulator fromthe sensor. The method includes terminating the electric stimulation ofthe portion of the neuromuscular system of the limb based on receivingthe second signal associated with the gait characteristic.

In some embodiments, a method of using an electric stimulator having asensor and an electrode assembly in electrical communication with aportion of a neuromuscular system of a limb includes receiving, at theelectric stimulator, a first signal that is sent from a control devicevia a first communication channel associated with a wirelesscommunication over a network. The first signal is associated with asystem parameter. A second signal is sent from the electric stimulatorto the control device via the first communication channel. The secondsignal is associated with a confirmation of the system parameter. Theelectric stimulator receives a third signal that is sent from the sensorvia a second communication channel, different from the firstcommunication channel. The third signal is associated with a gaitcharacteristic. The method includes sending, from the electricstimulator to the electrode assembly, a fourth signal. The fourth signalis operable to cause the electrode assembly to provide an electricstimulation to the portion of the neuromuscular system of the limb basedat least in part on the system parameter and the gait characteristic.

As used in this specification and the appended claims, the singularforms “a,” “an” and “the” include plural referents unless the contextclearly dictates otherwise. Thus, for example, the term “a member” isintended to mean a single member or a combination of members, “amaterial” is intended to mean one or more materials, or a combinationthereof.

As used herein, the term “limb segment” refers to at least a portion ofa mammalian appendage. For example, the embodiments described herein canbe coupled to and/or otherwise placed in contact with a limb segmentthat can include a portion of the upper and/or lower arm, or a portionof the upper and/or lower leg of a human body.

As used herein, the terms “envelop,” “enveloping,” and/or the like, withregard to a limb segment and an article or device coupled thereto, referto an article or device that substantially surrounds and/or covers atleast one half the circumference of a limb segment when coupled thereto.For example, if when coupled to a limb segment, an article or devicesubstantially circumscribes a portion of the limb segment, the articleor device can be said to envelop the portion of the limb segment.

As used herein, the terms “FES orthosis,” “orthosis,” “neuroprosthetic,”“FES device,” “device,” and/or the like can be used interchangeably andrefer generally to a medical apparatus that is selectively placed incontact with a portion of a patient. As described herein, such devicescan include one or more electrodes that can transmit a flow ofelectrical current to a portion of a neuromuscular system associatedwith the portion of the patient, thereby providing functional electricalstimulation to, for example, an impaired limb.

As used herein, the terms “reversible,” “reversibly,” and/or the likewhen used to described a process and/or procedure generally refer to anon-destructive process or procedure that can be subsequently undone bya similar yet substantially opposed, inverse, and/or oppositenon-destructive process or procedure. When used herein with respect toattachment and/or detachment of an element or assembly, a reversibleattachment refers to a non-destructive, repeatable attachment and/ordetachment of the element or assembly.

As used herein, the term “set” can refer to multiple features or asingular feature with multiple parts. For example, when referring to aset of walls, the set of walls can be considered as one wall withmultiple portions, or the set of walls can be considered as multiple,distinct walls. Thus, a monolithically constructed item can include aset of walls. Such a set of walls may include multiple portions that areeither continuous or discontinuous from each other. A set of walls canalso be fabricated from multiple items that are produced separately andare later joined together (e.g., via a weld, an adhesive, or anysuitable method).

As used herein, the terms “about” and “approximately” generally meanplus or minus 10% of the value stated, unless the context clearlyexpresses otherwise. For example, about 0.5 would include 0.45 and 0.55,about 10 would include 9 to 11, about 1000 would include 900 to 1100. Insome instances, such as when assessing a gait phase of a stimulationparameter and/or the like, the terms about and approximately cangenerally mean greater than plus or minus 10% of the value stated.

As used herein, the terms “communication channel,” “communication mode,”and/or “modality” can be used interchangeably and refer generally to oneor more modes of communication using, for example, one or moreelectronic devices. Such modes of communication can be associated with aspecific format (e.g., a data unit format) that, in some instances, canbe unique to that mode of communication (e.g., a different protocol, adifferent data unit structure or arrangement, etc.). For example, acellular telephone (e.g., a smart phone) can send a communication toanother electronic device such as an electric stimulator via a modalityand/or via a network that is associated with the cellular telephone(e.g., a short message service (SMS) modality, a multimedia messageservice (MMS) modality, a Bluetooth® modality, a wireless fidelity(WiFi®) modality, etc.). Thus, when referring to a channel and/ormodality, the channel and/or modality includes, defines, and/orotherwise is associated with a data unit format suitable fortransmission of data via that communication mode.

As used herein, the term “module” refers to any assembly and/or set ofoperatively-coupled electrical components that can include, for example,a memory, a processor, electrical traces, optical connectors, software(executing in hardware), and/or the like. For example, a module executedin the processor can be any combination of hardware-based modules (e.g.,a field-programmable gate array (FPGA), an application specificintegrated circuit (ASIC), a digital signal processor (DSP)) and/orsoftware-based modules (e.g., a module of computer code stored in memoryand/or executed at the processor) capable of performing one or morespecific functions associated with that module.

FIG. 1 is a schematic illustration of a system 100 used for gaitmodulation according to an embodiment. For example, in some instances,the system 100 can be used by a human patient who has one or moreimpaired limbs as a result of injury and/or disease (e.g., stroke,spinal cord injury, head injury, cerebral palsy, multiple sclerosis,etc.). More specifically, the system 100 includes a functionalelectrical stimulation (FES) orthosis 105 (also referred to herein as“orthosis” and/or “device”) that is placed in physical and electricalcontact with a limb 10 of the patient such as, for example, a lower limbsegment of an impaired leg. As such, the patient and/or a health careprofessional (e.g., doctor, nurse, technician, physician, physicaltherapist, etc.) can engage the system 100 in such a manner as to causethe orthosis 105 to selectively provide electrical stimulation to aportion of a neuromuscular system of the limb 10, which can, in turn,facilitate gait of the patient who might otherwise experience, forexample, drop foot or the like, as described in further detail herein.

The orthosis 105 includes a frame 110, an electrode assembly 120, one ormore sensors 130, and an electrical stimulator 140. In some embodiments,at least a portion of the orthosis 105 can be substantially similar inform and function as those described in U.S. Pat. No. 7,899,556entitled, “Gait Modulation System and Method,” filed Apr. 27, 2006(referred to henceforth as the “'556 patent”), U.S. Pat. No. 8,209,036entitled, “Gait Modulation System and Method,” filed Nov. 12, 2006(referred to henceforth as the “'036 patent”), and U.S. patentapplication Ser. No. 13/532,597 entitled, “Gait Modulation System andMethod,” filed Jun. 25, 2012 (referred to henceforth as the “'597application”), the disclosures of which are incorporated herein byreference in their entireties.

At least a portion of the frame 110 can be formed from a semi-rigidmaterial such as, for example, a relatively thin metal, a thermoplastic,a polymer, and/or the like, which can enable the frame 110 to providestructural support for the orthosis 105. The frame 110 can have anysuitable shape and/or size that can be, for example, associated with asegment of the limb 10 (e.g., a lower segment of a patient's leg).Moreover, at least a portion of the frame 110 can be transitionedbetween a first configuration and a second configuration to couple theframe 110 to the limb 10. For example, in some embodiments, the frame110 can include a coupling portion or the like that can be transitionedbetween a first (e.g., open) configuration and a second (e.g., closed)configuration to at least temporarily couple the frame 110 to the limb10. Expanding further, when the orthosis 105 is coupled to the limb 10,the frame 110 can be configured to substantially envelop and/orcircumscribe the limb 10. In some embodiments, the coupling portion canbe one or more straps, clips, ratchets, and/or the like that can allowfor facile placement and coupling to the frame 110 to the limb 10, asdescribed in further detail herein.

The electrode assembly 120 of the orthosis 105 is coupled to an innersurface of the frame 110. As such, when the frame 110 is coupled to thelimb 10 (e.g., transitioned from its first configuration to its secondconfiguration), at least a portion of the electrode assembly 120 isplaced in contact with a surface of the limb 10, as described in furtherdetail herein. The electrode assembly 120 can be any suitablearrangement of hardware and/or software. For example, in someembodiments, the electrode assembly 120 can include one or moreelectrodes that are each electrically coupled to a wire, electricaltrace, and/or the like that are operable in electrically coupling theone or more electrodes to the electric stimulator 140. In someembodiments, at least a portion of the electrode assembly 120 can bedisposed within a portion of the frame 110. For example, in suchembodiments, the electrode assembly can include a set of wires that aresubstantially enclosed by a portion of the frame 110. The wires caninclude end portions that each include a connector or the like that can,for example, be electrically coupled to the electric stimulator 140 at afirst end portion and that can, for example, be electrically coupled tothe electrodes at a second end portion. In some embodiments, theelectrode assembly 120 can be substantially similar in form and functionas those described in the '556 patent, the '036 patent, and/or the '597application.

The sensor 130 of the orthosis 105 can be any suitable sensor device orcan include a combination of sensor devices. For example, in someembodiments, the sensor 130 can include a tilt sensor, an accelerometer,a gyroscope, a pressure sensor, a speedometer, and/or the like. In thismanner, when the system 100 is used for gait modulation of a patientwith an impaired limb (i.e., leg), the sensor 130 can be configured tosense and/or otherwise detect a characteristic associated with, forexample, a gait event such as position of the sensor 130 relative to theorthosis 105, position of the limb 10 relative to a reference plane orthe like, angular position of the limb 10 relative to a reference planeor the like, velocity, rate of change in velocity (i.e., acceleration),tilt of the patient's foot, pressure (e.g., when the foot and/or shoecontacts a surface upon which the patient is walking), etc.

In some embodiments, the sensor 130 can be included in and/or integratedwith the frame 110, the electrode assembly 120, and/or the electricstimulator 140. In other embodiments, the sensor 130 can be physicallydistinct from the orthosis 105 and in electrical communication with theelectric stimulator 140 via a wireless communication channel. Forexample, in some embodiments, the electric stimulator 140 can be coupledto the frame 110, which in turn, is coupled to a first segment of thelimb (e.g., adjacent to the knee of the patient's leg) and the sensor130 can be coupled to and/or otherwise can be associated with a secondsegment of the limb 10 (e.g., adjacent to the foot and/or ankle of thepatient's impaired leg). In some embodiments, the sensor 130 can becoupled and/or otherwise can be associated with a segment of thecontralateral leg (e.g., adjacent to the foot and/or ankle of thepatient's leg not donning the electric stimulator 140). In someembodiments, the system 100 can include multiple distinct sensors 130.For example, in some embodiments, the system 100 can include a firstsensor that is integrated with the electric stimulator 140 and a secondsensor that is physically distinct from, yet in electrical communicationwith, the electric stimulator 140 (e.g., disposed within and/or coupledto a shoe of the patient). In such embodiments, the electricalstimulator 140 can be configured to receive signals from and/or sendsignals to the first sensor via a first communication channel,associated with a wired signal transmission (e.g., signals transmittedalong a wire or signal trace), and a second communication channel,associated with a wireless signal transmission (e.g., WiFi®, Bluetooth®,etc.), as described in further detail herein.

The electric stimulator 140 of the orthosis 105 can be any suitablefunctional electrical stimulation device having any combination ofhardware and software. For example, the electric stimulator 140 can bean electronic device that can include one or more electrical circuitsoperable in providing a flow of electrical current to at least a portionof the neuromuscular system of the limb 10. The electric stimulator 140of the orthosis 105 is removably coupled to the frame 110. For example,in some embodiments, the frame 110 can form a cradle and/or the likethat can be configured to at least temporarily retain the electricalstimulator 140 therein, as described below with respect to specificembodiments. Moreover, the electric stimulator 140 is configured to beplaced in electrical communication with the electrode assembly 120 andthe sensor 130. In some embodiments, the electrode assembly 120 and/orthe sensor 130 can be included in (e.g., integrated with) the electricstimulator 140. In other embodiments, the electrode assembly 120 and thesensor 130 can be operably coupled to the electric stimulator 140 viaany suitable wiring, connector, interface, and/or structure. Forexample, in some embodiments, the frame 110 can include a connectorand/or the like configured to place the electric stimulator 140 inelectrical communication with, for example, the electrode assembly 120and/or the sensor 130.

In some embodiments, the electric stimulator 140 can receive and/or sendsignals to a set of external and/or implanted electrical devices via anysuitable communication mode. For example, in some embodiments, theelectric stimulator 140 can include two, three, four, five, six, or morecommunication and/or electrical channels that can be operable in sendingand/or receiving signals to and/or from, respectively, the electrodeassembly 120, the sensor 130, and/or any other suitable electronicdevice operably coupled thereto. In some embodiments, at least a portionof the communication and/or electrical channels can be associated withsending and/or receiving signal via a wireless communication modality(e.g., a modality, format, and/or the like associated with WiFi®,Bluetooth®, near field communication (NFC), cellular communication suchas, short message service (SMS) or multimedia message service (MMS),and/or the like), as described in further detail herein.

As described above, in some instances, the system 100 can be used forgait modulation of patients with an impaired limb. More specifically,the system 100 can be used to enhance the limb function of a patientexperiencing drop foot. In such instances, the patient can manipulatethe orthosis 105 in such a manner as to couple the orthosis 105 to theimpaired limb. For example, the patient can position the orthosis 105adjacent to the knee of an impaired leg and can transition the frame 110from a first configuration to a second configuration (as describedabove) to removably couple the orthosis 105 to the leg. The placement ofthe orthosis 105 can be such that a set of electrodes included in theelectrode assembly 120 are disposed in a location relative to the legthat is associated and/or corresponds to a desired portion of theneuromuscular system of the leg. More specifically, to enhance the legfunction of a patient experiencing drop foot during gait, the orthosis105 can be positioned relative to the leg to place the electrodes inelectric communication with the peroneal nerve and/or the tibial nerve.Thus, the electrodes can transmit functional electrical stimulation tothe peroneal nerve, which can result in dorsiflexion of the foot, and/orthe tibial nerve, which can result in plantarflexion of the foot,thereby enhancing the function of the impaired leg to mitigate theeffects of drop foot, as described in further detail herein.

With the frame 110 retained in the desired position relative to theimpaired leg, the patient can begin walking. During walking, the sensor130 can be configured to sense and/or detect a set of characteristics(such as those described above) associated with a gait event and cansend a signal associated with the characteristic to the electricstimulator 140. For example, in some embodiments, the gait event can beassociated with a “heel-off” event (i.e., the point during gait at whichthe heel is lifted off the surface upon which the patient is walking).The sensor 130 can send the signal to the electric stimulator 140 viaany suitable communication channel. For example, if the sensor 130 iscollocated with at least a portion of the electric stimulator 140 and/orthe frame 110, the sensor 130 can send the signal via a communicationchannel associated with a wired signal transmission. If, however, thesensor 130 is physically distinct from the other portions of theorthosis 105, the sensor can send the signal via a communication channelassociated with a wireless signal transmission, such as those describedabove. In some embodiments, the electric stimulator 140 can receive asignal from multiple sensors 130 that can be configured to sense and/ordetect a characteristic associated with a gait event at differentsegments along the leg of the patient.

Upon receiving the signal from the sensor 130, the electric stimulator140 can be configured to transmit an electrical current resulting from arelatively high voltage (e.g., generated by a power supply or the likeincluded in the electric stimulator 140) along an electric circuit thatis electrically coupled to the electrode assembly 120. Thus, the currentresulting from the relatively high voltage (also referred to herein as“high current”) is transmitted to the electrodes of the electrodeassembly 120, which in turn, provide FES to the peroneal nerve, therebyresulting in dorsiflexion and/or plantarflexion of the footsubstantially at the time of the heel-off event (e.g., a very short timeafter the sensor 130 detects the heel-off event consistent with a rateof electrical signal and/or electrical current transmission such as,0.10 seconds, 0.05 seconds, 0.01 seconds, 0.001 seconds, 0.0001 seconds,or less). As a result, the foot of the patient flexes toward the leg,enhancing a portion of the patient's gait.

In some instances, the sensor 130 can sense and/or detect acharacteristic associated with a second gait event such as, for example,a “heel-on” event (i.e., the point during gait at which the heel isplaced in contact with the surface of upon which the patient iswalking). As described above, the sensor 130 can send a signalassociated with the characteristic to the electric stimulator 140 and,upon receipt, the electric stimulator 140 can terminate the flow of therelatively high current to the electrodes in electrical contact with theperoneal nerve. In some instances and in a substantially concurrentprocess, the electric stimulator 140 can generate a relatively highcurrent along an electric circuit that is electrically coupled to one ormore electrodes in electrical communication with the tibial nerve. Thus,the electrodes can provide FES to the tibial nerve resulting inplantarflexion of the foot substantially at the time of the heel-onevent (as described above). In this manner, the termination of the FESto the peroneal nerve relaxes the portion of the neuromuscular systemresulting in a relaxation of the dorsiflexion, while substantiallyconcurrently, the FES provided to the tibial nerve results inplantarflexion of the foot. As such, the foot flexes away from the leg,enhancing a portion of the patient's gait.

In some embodiments, the electric stimulator 140 can include, forexample, a memory or the like that can be configured to storeinformation at least partially defining a set parameters associated withthe FES. For example, in some embodiments, the electrical stimulator 140can be configured to store information associated with a voltage and/orcurrent level associated with the FES, a sensitivity associated with thesensor 130, a repository of actions to perform based on informationreceived from the sensor 130, and/or any other suitable informationand/or logic. Thus, the electric stimulator 140 can be configured toprovide FES to the impaired leg with a set of characteristics that canbe uniquely associated with the patient. In some instances, the patientand/or a health care professional can manipulate the electric stimulator140 to change one or more parameters and/or characteristics associatedwith the FES provided to the impaired leg.

As shown in FIG. 1, in some embodiments, the electric stimulator 140 canbe in communication with a control device 160. The control device 160can be any suitable electronic device that can provide an interface fora user (e.g., the patient and/or a health care professional) tomanipulate one or more characteristics and/or parameters associated withthe FES. For example, in some embodiments, the control device 160 canbe, for example, a personal computer (PC), a personal digital assistant(PDA), a smart phone, a laptop, a tablet PC, a server device, aworkstation, and/or the like. The electronic device can include at leasta memory (e.g., a random access memory (RAM), a memory buffer, a harddrive, a read-only memory (ROM), an erasable programmable read-onlymemory (EPROM), and/or the like); a processor (e.g., a general purposeprocessor, a central processing unit (CPU), an accelerated processingunit (APU), and Application Specific Integrated Circuit (ASIC), and/orthe like); a network interface (e.g., a network interface card and/orthe like that can include at least an Ethernet port and/or a wirelessradio (e.g., a WiFi® radio, a Bluetooth® radio, etc.)); and an outputdevice (e.g., a display such as a cathode ray tube (CRT) monitor, aliquid crystal display (LCD) monitor, a light emitting diode (LED)monitor, and/or the like, a Universal Serial Bus (USB) drive, an ANT+compatible device or application, and/or any other suitable outputdevice). In this manner, the control device 160 can be in communicationwith the electric stimulator 140 via the network interface and theprocessor can be configured to run or execute a set of instructions orcode stored in the memory associated with using, for example, a PCapplication, a mobile application, an internet web browser, a cellularand/or wireless communication (via a network), and/or the like tocommunicate with and/or otherwise control at least a portion of theelectric stimulator 140, as described herein with respect to specificembodiments.

FIGS. 2-8 are illustrations of a system 200 used, for example, in gaitmodulation according to an embodiment. For example, in some instances,the system 200 can be used by a human patient who has one or moreimpaired limbs as a result of injury and/or disease (e.g., stroke,spinal cord injury, head injury, cerebral palsy, multiple sclerosis,etc.). More specifically, the system 200 includes a functionalelectrical stimulation (FES) orthosis 205 (also referred to herein as“orthosis” and/or “device”) that is placed in physical and electricalcontact with, for example, a lower limb segment of an impaired leg 20(see e.g., FIG. 4). In some embodiments, at least a portion of theorthosis 205 can be substantially similar in form and/or function tothose described in the '556 patent, the '036 patent, and the '597application incorporated by reference in their entireties above. Assuch, the patient and/or a health care professional (e.g., doctor,nurse, technician, physician, physical therapist, etc.) can engage thesystem 200 in such a manner as to cause the orthosis 205 to selectivelyprovide functional electrical stimulation to a portion of aneuromuscular system of the leg 20, which can, in turn, facilitate gaitof the patient who might otherwise experience, for example, drop foot orthe like, as described in further detail herein.

As shown in FIGS. 2-7, the orthosis 205 includes a frame 210, anelectrode assembly 220, and an electrical stimulator 240. Although notshown in FIGS. 2-7, the orthosis 205 can also include and/or otherwisebe operably coupled to one or more sensors 230, as shown and describedherein with reference to FIGS. 7 and 8. The frame 210 of the orthosis205 can have any suitable shape and/or size that can be, for example,associated with a segment of the leg 20 and includes at least a portionthat can be transitioned between a first configuration and a secondconfiguration to couple the frame 210 to the leg 20. In someembodiments, the frame 210 can have a shape and size that are associatedwith a portion of the lower leg (e.g., between the knee and the foot ofthe lower leg). As such, an upper portion of the frame 210 can form anergonomic contour that can, for example, substantially correspond with ashape of an inferior border of a patella 21 of a knee of the leg 20 (seee.g., FIG. 4). Moreover, the frame 210 can define an ergonomiccross-sectional shape taken about a plane that is normal to alongitudinal axis of the frame 210 (e.g., substantially coaxial with anaxis defined by the segment of the leg 20) that corresponds to and/orotherwise is associated with a shape of a tibial crest 22 of the lowerleg (see e.g., FIG. 4). In some embodiments, the frame 210 can besubstantially similar in form and/or function as those described in the'556 patent, the '036 patent, and/or the '597 patent.

As shown in FIGS. 2-5, the frame 210 includes an inner structure 211, acradle 212, a coupling portion 214, and a cover 216. At least a portionof the inner structure 211 can be formed from a semi-rigid material suchas, for example, a relatively thin metal, a thermoplastic, a polymer,and/or the like. In this manner, the inner structure 211 can besufficiently rigid to provide structural support for the orthosis 205,while being sufficiently flexible to allow the limb about which theinner structure 211 is disposed to increase or decrease during, forexample, muscle flexion or muscle relaxation, respectively. As shown inFIG. 3, the inner structure 211 can be substantially C-shaped such as toallow the inner structure 211 to expand and contract in response to theexpansion and contraction of the leg 20, respectively. Moreover, thearrangement of the inner structure 211 can be such that when the size ofthe leg 20 is reduced (e.g., after expansion due to muscle flexion), therigidity of the inner structure 211 can be sufficient to transition theinner structure 211 to a size and shape associated with the reduced sizeof the leg 20. Similarly stated, the inner structure 211 be biased suchthat when an external force expands the inner structure 211 to anexpanded size is removed, the inner structure 211 returns to anunexpanded size, smaller than the expanded size. Thus, this arrangementenables the frame 210 to substantially envelop the portion of the leg20, and serves to effectively disperse a pressure and/or strain thatwould otherwise be exerted on the portion of the leg 20, therebyretaining the natural profile and geometry of the leg 20 tissue and/ormuscles when coupled thereto. In some embodiments, the inner structure210 can be substantially similar in form and/or function as a centralframe described in the '556 patent, the '036 patent, and/or the '597patent.

The cradle 212 of the frame 210 extends from the inner structure 211 todefine a recess within which the electric stimulator 240 can bedisposed. Similarly stated, the cradle 212 includes and/or is otherwiseformed by a relatively thin set of walls extending from an outer surfaceof the inner structure 211 that have a size and a shape that areassociated with the electric stimulator 240. The cradle 212 can includeany suitable surface finish, protrusion, detent, etc. that can act to atleast temporarily retain the electric stimulator 240 within the wallsforming the cradle 212. For example, in some embodiments, the cradle 212can form and/or define a set of detents that can matingly receive a setof corresponding protrusions extending from an outer surface of theelectric stimulator 240 when therein (or vice versa). In otherembodiments, an inner surface of the cradle 212 can have a finish and/orcan be formed from a material with a relatively high coefficient offriction. Thus, when the electric stimulator 240 is disposed within thecradle 212 an outer surface of the electric stimulator 240 and an innersurface of the cradle 212 can form and/or define a friction fit that canat least temporarily retain the electric stimulator 240 in the cradle212. As shown in FIGS. 3 and 4, the cradle 212 includes and/or forms aconnector 213 that can be electrically coupled to a correspondingconnector (not shown in FIGS. 2-8) of the electric stimulator 240.Moreover, the connector 213 is electrically coupled to a connector 222of the electrode assembly 220 (described in further detail herein).Therefore, when the electric stimulator 240 is positioned within thecradle 212, the connector 213 can place the electric stimulator 240 inelectrical communication with the electrode assembly 220, as describedin further detail herein. Although described above as electricallyconnecting the electric stimulator 240 to the electrode assembly 220, insome embodiments, the connector 213 can be configured to electricallyconnect any number of electrical devices (e.g., one or more sensorsand/or the like) to the electric stimulator 240 and/or the electrodeassembly 220.

The coupling portion 214 of the frame 210 can be transitioned between afirst (e.g., open) configuration and a second (e.g., closed)configuration to reversibly couple the frame 210 to the leg 20. Saidanother way, the frame 210 can be positioned about a portion of the leg20 and the coupling portion 214 can be transitioned to the secondconfiguration to removably couple (i.e., at least temporarily couple)the frame 210 to the leg 20, as shown in FIG. 4. The coupling portion214 includes substantially parallel, modular straps (e.g., elasticstraps, inelastic straps, and/or straps including one or more elasticportions and one or more inelastic portions) connecting between theframe 210 and a handle 215. The arrangement of the coupling portion 214is such that during donning, the straps wrap circumferentially aroundthe limb segment (e.g., the leg 20), to securely couple the orthosis 205to the limb segment. In some embodiments, the handle 215 can form and/orprovide a structure that can facilitate the engagement of the couplingportion 214. For example, in some embodiments, the handle can facilitatethe engagement and/or manipulation of the coupling portion 214 by apatient who may have impairment in one or both hands.

The cover 216 of the frame 210 can be configured to substantiallyenclose the inner structure 211 and includes an (see e.g., FIGS. 2 and6). The cover 216 can be formed from any suitable material and/orcombination of materials. For example, in some embodiments, the cover216 can be formed from a relatively flexible and/or soft material thatcan elastically deform when exposed to an external force. In someembodiments, the cover 216 can be, for example, over-molded about theinner structure 211. In other embodiments, the cover 216 can beremovably disposed about the inner structure 211. In this manner, thecover 216 can enhance the ergonomics (e.g., comfort) of the frame 210 byforming a relatively flexible and/or soft layer that is placed incontact with the patient.

As shown in FIGS. 5 and 6, the cover 216 includes one or more couplers217 that can engage a portion of the electrode assembly 220. Thecouplers 217 can be any suitable shape, size, or configuration. Forexample, in some embodiments, the couplers 217 can form a button, asnap, a detent, a protrusion, one half of a hook-and-loop coupler (i.e.,Velcro®), and/or the like. As such, the couplers 217 can each bematingly placed in contact with a corresponding portion of a differentelectrode 221 included in the electrode assembly 220 to at leasttemporarily retain the electrodes 221 in a substantially fixed positionrelative to the frame 210. In some embodiments, the position of thecouplers 217, and hence the electrodes 221 coupled thereto, can beassociated with a target portion of the neuromuscular system of the leg20 such as, for example, the peroneal nerve and/or the tibial nerve.Thus, when the electric stimulator 240 is disposed in the cradle 212 ofthe frame 210, the connector 213 of the inner structure 211 and theconnector 222 of the electrode assembly 220 (described above)electrically couple the electric stimulator 240 to the electrodes 221such that a relatively high current can flow from the electricstimulator 240 and through the electrodes 221 to provide functionalelectrical stimulation to the portion of the neuromuscular system of theleg 20, as described in further detail herein.

Although the electrodes 221 are particularly shown and described withreference to FIGS. 5 and 6, in other embodiments, the electrodes 221 canbe any suitable configuration. For example, in some embodiments, theorthosis 205 can include one, two, three, four, five, six, or moreelectrodes disposed at different positions along the inner surface ofthe cover 216. Moreover, while the inner surface of the cover 216 isshown as including discrete couplers 217, in other embodiments, anynumber of electrodes 221 can be coupled directly to the inner surfaceand retained in a substantially fixed position relative to the frame210. In some embodiments, the electrodes 221 and/or the electrodeassembly 220 can be substantially similar in form and function as thosedescribed in the '556 patent, the '036 patent, and/or the '597 patent.

The sensor 230 (see e.g., FIG. 7) of the orthosis 205 can be anysuitable sensor device or can include a combination of sensor devices.For example, in some embodiments, the sensor 230 can include a tiltsensor, an accelerometer, a gyroscope, a pressure sensor, a speedometer,and/or the like. In this manner, when the system 200 is used for gaitmodulation of a patient with the impaired leg 20, the sensor 230 can beconfigured to sense and/or otherwise detect a characteristic associatedwith, for example, a gait event such as position of the sensor 230relative to the orthosis 205, position of the leg 20 relative to areference plane or the like, angular position of the leg 20 relative toa reference plane or the like, velocity, rate of change in velocity(i.e., acceleration), tilt of the patient's foot, pressure (e.g., whenthe foot and/or shoe contacts a surface upon which the patient iswalking), etc.

As described above, in some embodiments, the sensor 230 can be includedin and/or integrated with the frame 210, the electrode assembly 220,and/or the electric stimulator 240. In other embodiments, the sensor 230can be physically distinct from the orthosis 205 and in electricalcommunication with the electric stimulator 240 via a wirelesscommunication channel. For example, in some embodiments, the electricstimulator 240 can be coupled to the frame 210, which in turn, iscoupled to a first segment of the leg 20 (e.g., adjacent to the knee ofthe patient as shown in FIG. 4) and the sensor 230 can be coupled toand/or otherwise can be associated with a second segment of the leg 20(e.g., adjacent to the foot and/or ankle of the patient's impaired leg).By way of example, the sensor 230 can be at least temporarily coupledthe patient's shoe worn on the foot of the impaired leg 20 (see e.g.,FIG. 8). In some embodiments, the sensor 230 can be coupled and/orotherwise can be associated with a segment of the contralateral leg(e.g., adjacent to the foot and/or ankle of the patient's leg notdonning the electric stimulator 240). In some embodiments, the system200 can include multiple distinct sensors 230. For example, in someembodiments, the system 200 can include a first sensor that isintegrated with the electric stimulator 240 and a second sensor that isphysically distinct from, yet in electrical communication with, theelectric stimulator 240 (e.g., disposed within and/or coupled to a shoeof the patient). In such embodiments, the electrical stimulator 240 canbe configured to receive signals from and/or send signals to the firstsensor via a first communication channel, associated with a wired signaltransmission (e.g., signals transmitted along a wire or signal trace),and a second communication channel, associated with a wireless signaltransmission (e.g., WiFi®, Bluetooth®, etc.), as described in furtherdetail herein.

In some embodiments, the sensor 230 can be substantially similar in formand/or function as those described in U.S. Pat. No. 7,632,239 entitled,“Sensor Device for Gait Enhancement,” filed Oct. 23, 2006, U.S. Pat. No.8,382,688 entitled, “Sensor Device for Gait Enhancement,” filed Dec. 4,2009, and U.S. Patent Application Publication No. 2009/0069865 entitled,“Functional Electrical Stimulation Systems,” filed May 1, 2007, thedisclosures of which are incorporated herein by reference in theirentireties.

The electric stimulator 240 can be any suitable electronic deviceconfigured to generate a flow of a relatively high current. As describedabove, the electric stimulator 240 can be positioned within the cradle212 of the frame 210 to at least temporarily couple the electricstimulator 240 thereto. As shown in FIG. 7, the electric stimulator 240includes a battery 242 and a power supply 243 that are in electricalcommunication with a high voltage circuit 244, a digital circuit 245,and a stimulation circuit 249. The battery 242 can be any suitablebattery and/or other source of electrical power. For example, in someembodiments, the battery 242 can be a relatively low profilerechargeable battery (e.g., a coin battery or the like). Similarly, thepower supply 243 can be any suitable power supply, converter,conditioner, inverter, capacitor, and/or the like. The power supply 243can be electrically coupled to the battery 242 via any suitable circuitand/or interface. In this manner, the power supply 243 can receive aflow of electrical current from the battery 242 and convert, amplify,condition, and/or otherwise change one or more attributes associatedwith the electrical current received from the battery 242. For example,in some embodiments, the power supply 243 can be configured to increasea voltage associated with at least a portion of the electrical currentreceived from the battery 242.

In some embodiments, the power supply 243 can receive electrical currentfrom the battery 242 and can, for example, increase and/or convert avoltage of a first portion of the electrical current by a first amount(e.g., to a first voltage), and increase and/or convert a voltage of asecond portion of the electrical current by a second amount (e.g., to asecond voltage), less than the first amount. In such embodiments, thepower supply 243 can include a first electrical circuit (not shown inFIG. 7) that is associated with the first voltage (i.e., the highervoltage) and that is electrically coupled to the high voltage circuit244. Similarly, the power supply 243 can include a second electricalcircuit (not shown in FIG. 7) that is associated with the second voltage(i.e., the lower voltage) and that is electrically coupled to thedigital circuit 246. Thus, the power supply 243 can receive a flow ofcurrent from the battery 242 and can convert the flow of current into afirst portion having a relatively high voltage suitable for the highvoltage circuit and a second portion having a relatively low voltagesuitable for the digital circuit.

The high voltage circuit 244 can include any suitable electricalcomponent. For example, although not shown in FIG. 7, the high voltagecircuit 244 can include a capacitor, resistor, logic gate, wire,electrical trace, and/or the like. The high voltage circuit 244 is inelectrical communication with the stimulation circuit 245 and isconfigured to provide a flow of electrical current having the relativelyhigh voltage (described above) thereto.

The digital circuit 245 can be any suitable electrical circuit includingany suitable electrical component. For example, as shown in FIG. 7, thedigital circuit 245 includes at least a memory 246, a processor 247, anda communication device 248 that are each electrically coupled via, forexample, a set of wires, signal traces, and/or the like (not shown inFIG. 7). Although not shown in FIG. 7, the digital circuit 245 can alsoinclude one or more sensors 230 that can be in electrical communicationwith the memory 246, the processor 247, and/or the communication device248 via the set of wires, signal traces, and/or the like. Moreover, thecomponents of the digital circuit 245 can be in electrically coupled tothe power supply 243 via one or more wires, signal traces, and/or thelike.

The memory 246 can be, for example, a random access memory (RAM), amemory buffer, a hard drive, a read-only memory (ROM), an erasableprogrammable read-only memory (EPROM), and/or the like. In someembodiments, the memory 246 can be configured to store, for example, oneor more modules that can include instructions to cause the processor 247to perform one or more processes, functions, and/or the like. Forexample, in some embodiments, the memory 246 can store instructionsand/or code representing one or more parameters associated withproviding FES to a patient, as described in further detail herein.

The processor 247 of the digital circuit 245 can be any suitableprocessing device configured to run and/or execute a set of instructionsor code such as, for example, a general purpose processor (GPU), acentral processing unit (CPU), an accelerated processing unit (APU), anapplication specific integrated circuit (ASIC), a front end processor, afield programmable gate array (FPGA), and/or the like. As such, thememory 246 can store instructions to cause the processor 247 to executemodules, processes, and/or functions associated with providing FES tothe patient. In this manner, based on the instructions stored by thememory 246, the processor 247 can change, modify, update, and/orotherwise control one or more parameters associated with FES. Forexample, in some instances, the memory 246 can include instructions tocause the processor 247 to perform one or more functions, processes,and/or modules based on receiving a signal from the sensor 230 (e.g., incommunication with the digital circuit 245, as described in furtherdetail herein). In some such instances, the functions, processes, and/ormodules can be operable in providing and/or terminating a flow ofrelatively high current to the electrode assembly 220, as described infurther detail herein.

The communication device 248 of the digital circuit 245 can be anysuitable device that can communicate with one or more electricalcomponents and/or with one or more networks. For example, thecommunication device 248 can include one or more wired and/or wirelessinterfaces, such as, for example, Ethernet interfaces, optical carrier(OC) interfaces, and/or asynchronous transfer mode (ATM) interfaces. Insome embodiments, the communication device 248 can be, for example, anetwork interface card and/or the like that can include at least anEthernet port and/or a wireless radio (e.g., a WiFi® radio, a Bluetooth®radio, cellular network radio (e.g., global system for mobilecommunications (GSM), personal communications service (PCS), digitaladvanced mobile phone service (D-AMPS), etc.). In this manner, thecommunication device 248 can be configured to place the orthosis 205 inelectrical communication (e.g., via a wired or wireless connection) withany suitable external device such as, for example, a control device, asensor, a second orthosis (similar to or different from the orthosis205), and/or the like via one or more networks. Such a network can be,for example, a local area network (LAN), a wide area network (WAN), ametropolitan area network (MAN), a worldwide interoperability formicrowave access network (WiMAX), a telephone network, an intranet, theInternet, an optical fiber (or fiber optic)-based network, a virtualnetwork, a cellular network (e.g., GSM, PCS, D-AMPS, etc.), and/or anyother suitable network. By way of example, in some embodiments, thecommunication device 248 can be configured to receive signals fromand/or send signals to the sensor 230 coupled to the shoe worn on thefoot of the impaired leg 20 via Bluetooth® (see e.g., FIG. 8).

As shown in FIG. 7, the stimulation circuit 249 is in electricalcommunication with the high voltage circuit 244 and the digital circuit245. The stimulation circuit 249 can include any suitable electricalcomponent. For example, although not shown in FIG. 7, the stimulationcircuit 249 can include a capacitor, a resistor, a logic gate, a wire,an electrical trace, and/or the like. Moreover, the stimulation circuit249 is electrically coupled to the electrode assembly 220. In thismanner, the stimulator circuit 249 can receive a flow of relatively highcurrent and can transmit the relatively high current to the electrodes221 to, for example, provide FES to the leg 20. In some embodiments, thedigital circuit 245 can be configured to send a signal to thestimulation circuit 249 that can, for example, control the output of thestimulation circuit 249. For example, the stimulation circuit 249 caninclude a component, processor, logic gate, and/or the like that canoperable in switch the stimulation circuit 249 between a firstconfiguration and a second configuration based on receiving or notreceiving a signal from the digital circuit 245. By way of example, thefirst configuration can be associated with an open circuit or the likein which upon receiving the flow of current (i.e., the relatively highcurrent) from the high voltage circuit 244, the stimulation circuit 249does not transfer, transmit, and/or otherwise provide a flow ofrelatively high current to the electrode assembly 220. Conversely, thestimulation circuit 249 can receive a signal (e.g., a relatively lowvoltage electrical current signal) from the digital circuit 245 that canbe operable in switching the stimulation circuit to its secondconfiguration, which can be associated with a closed circuit or thelike. Thus, when in the second configuration and upon receiving the flowof current from the high voltage circuit 244, the closed stimulationcircuit 249 can transmit, transfer, and/or otherwise provide a flow ofrelatively high current to the electrode assembly 220. As such, theelectrode assembly 220 can provide FES (via the electrodes 221) to aportion of the neuromuscular system of the leg 20.

As described above, in some instances, the system 200 can be used forgait modulation of the patient having the impaired leg 20. Morespecifically, the system 200 can be used to enhance the leg 20 functionof the patient experiencing drop foot. In such instances, the patientcan manipulate the orthosis 205 in such a manner as to couple theorthosis 205 to the impaired leg 20. For example, the patient canposition the orthosis 205 adjacent to the patella 21 of the impaired leg20 and can transition the coupling portion 214 of the frame 210 from itsfirst configuration to its second configuration to removably couple theorthosis 205 to the leg 20, as described above with reference to FIG. 4.The placement of the orthosis 205 can be such that the electrodes 221included in the electrode assembly 220 are disposed in a locationrelative to the leg 20 that is associated with and/or corresponds to theperoneal nerve and/or the tibial nerve. Thus, the electrodes 221 cantransmit functional electrical stimulation to the peroneal nerve, whichcan result in dorsiflexion of the foot, and/or the tibial nerve, whichcan result in plantarflexion of the foot, thereby enhancing the functionof the impaired leg 20 to mitigate the effects of lower leg weakness,lower leg paralysis, and/or drop foot

With the frame 210 retained in the desired position relative to theimpaired leg 20 via the inner structure 211 and the coupling portion214, the patient can begin walking. During walking, the sensor 230 canbe configured to sense and/or detect a set of characteristics (such asthose described above) associated with a gait event and can send asignal associated with the characteristic to the electric stimulator240. For example, in some embodiments, the sensor 230 can be coupled toand/or disposed in a shoe worn on the foot of the impaired leg 20 andcan be configured to sense and/or detect a gait event associated with a“heel-off” event based at least in part on a change in pressure. Thesensor 230 can then send the signal to the electric stimulator 240 via,for example, a protected wireless communication channel.

In other embodiments, the sensor 230 can be collocated with at least aportion of the electric stimulator 240 and/or the frame 210. As such,the sensor 230 can be configured to sense and/or detect the “heel-off”event based at least in part on an acceleration, tilt, relativeposition, and/or movement of the sensor 230. In this manner, the sensor230 can send a signal via a communication channel associated with awired signal transmission to the electric stimulator 240. In still otherembodiments, the electric stimulator 240 can receive a signal frommultiple sensors 230 that can be configured to sense and/or detect acharacteristic associated with a gait event at different segments alongthe leg of the patient. For example, the electric stimulator 240 canreceive a signal from a collocated sensor 230 via a first communicationchannel associated with a wired signal transmission and can receive asignal from a physically distinct sensor 230 via a second communicationchannel associated with a wireless signal transmission such as, forexample, Bluetooth®.

In this manner, the communication device 248 of the electric stimulator240 can receive the signal from the sensor 230 and can forward thesignal and/or otherwise send a signal representing the received signalto the processor 247. Upon receipt, the processor 248 can determine,reference, and/or calculate one or more system parameters based at leastin part on information stored in the memory 246 and the signal sent fromthe sensor 230. In some instances, the processor 247 can perform one ormore processes, functions, modules and/or the like that can, forexample, cause the power supply 243 to generate and transmit arelatively high current along the high voltage circuit 244 to thestimulation circuit 249. In addition and substantially in a parallelprocess, the processor 247 can send a relatively low voltage electricalcurrent signal to the stimulation circuit 249 that can, for example,place the stimulation circuit 249 in a closed state or the like. Thus,the relatively high current is transmitted to the electrodes 221 of theelectrode assembly 220, which in turn provides FES to the peronealnerve, thereby resulting in dorsiflexion of the foot substantially atthe time of the heel-off event (e.g., a very short time after the sensor230 detects the heel-off event as described above). As a result, thefoot of the patient flexes toward the leg, enhancing a portion of thepatient's gait.

In some instances, the sensor 230 can sense and/or detect acharacteristic associated with a second gait event such as, for example,a “heel-on” event (i.e., the point during gait at which the heel isplaced in contact with the surface of upon which the patient iswalking). As described above, the sensor 230 can send a signalassociated with the characteristic to the electric stimulator 240 and,upon receipt, the processor 247 can send a signal to the power supply243 to terminate the flow of the relatively high current to the highvoltage circuit 244. In addition and in a substantially parallelprocess, the processor 247 can send a relatively low voltage electricalcurrent signal to the stimulation circuit 249 that can, for example,place the stimulation circuit 249 in an open circuit state or the like.Thus, current is no longer transferred to the electrodes 221 inelectrical contact with the peroneal nerve, thereby allowing theassociated muscles to relax, which in turn results in the foot moving ina direction away from the leg. In this manner, the FES provided to theperoneal nerve can facilitate the gait of the patient.

In other instances, the processor 247 need not send a signal to thepower supply 243 to terminate the flow of relatively high current to thehigh voltage circuit 244. For example, in such instances, thestimulation circuit 249 can define multiple electrical circuits betweenthe stimulation circuit 249 and different portions of the electrodeassembly 240. In this manner, the processor 247 can send a signal to thestimulation circuit 249 that can be operable in opening the electricalcircuit associated with the peroneal nerve, thereby terminating the FESprovided thereto, and can be operable in closing a different electricalcircuit associated with, for example, the tibial nerve. Thus, therelatively high current can flow along the now closed electric circuitthat is electrically coupled to one or more electrodes 221 in electricalcommunication with the tibial nerve. As such, the electrodes 221 canprovide FES to the tibial nerve resulting in plantarflexion of the footsubstantially at the time of the heel-on event (as described above).More specifically, the termination of the FES to the peroneal nerverelaxes the portion of the neuromuscular system resulting in arelaxation of the dorsiflexion, while substantially concurrently, theFES provided to the tibial nerve results in plantarflexion of the foot.As a result, the foot flexes away from the leg, enhancing the patient'sgait.

In some embodiments, the memory 246 of the digital circuit 245 can storeinformation at least partially defining a set parameters associated withthe FES. For example, in some embodiments, the memory 246 can storeinformation associated with a voltage and/or current level associatedwith the FES, a sensitivity associated with the sensor 230, a repositoryof actions to perform based on information received from the sensor 230,a skin sensitivity of the patient, and/or any other suitable informationand/or logic. Thus, the electric stimulator 240 can be configured toprovide FES to the impaired leg 20 with a set of characteristics thatcan be uniquely associated with the patient. In some instances, thepatient and/or a health care professional can manipulate the electricstimulator 240 to change one or more parameters and/or characteristicsassociated with the FES provided to the impaired leg 20. For example,although not shown in FIGS. 2-8, in some embodiments, the electricstimulator 240 can include an output device such as, for example, adisplay. In some instances, the display can, for example, provide a userinterface for the patient and/or the health care professional tomonitor, modify, and/or otherwise control the electric stimulator 240.

Although the electric stimulator 240 is described above as providing FESto, for example, a first portion of the neuromuscular system of thepatient, and upon receiving a signal from the sensor 230, terminatingthe FES to the first portion of the neuromuscular system and providingFES to, for example, a second portion of the neuromuscular system, inother embodiments, the electric stimulator 240 can be configured toprovide FES to the first portion and the second portion of theneuromuscular system in substantially concurrent and/or complementaryprocesses. Moreover, the processor 247 can be configured to performand/or execute one or more processes, functions, and/or modulesassociated with selectively modulating a flow of electrical current toone or more portions of the neuromuscular system. For example, in someembodiments, the electric stimulator 240 can be configured to provideFES to a portion of the peroneal nerve, which can result in dorsiflexionof the foot on an impaired leg. Based at least in part on a signalreceived from the sensor 230, the processor 247 can perform one or moreprocesses and/or functions that can, for example, reduce a voltage ofthe FES that is provided to the portion of the peroneal nerve, therebyreducing dorsiflexion of the foot. In a substantially parallel and/orconcurrent process, the processor 247 can execute one or more functionsthat can close a circuit (e.g., within the stimulation circuit 249) orthe like to provide FES to a second portion of the neuromuscular system(e.g., a second portion of the peroneal nerve and/or a portion of thetibial nerve) that can result in plantarflexion of the foot. In someinstances, a voltage associated with the FES provided to causeplantarflexion can be increased in a substantially concurrent and/orinversely proportional process as the decrease in the voltage of the FESprovided to cause dorsiflexion. In this manner, the processor 247 of theelectric stimulator 240 can be configured to direct, divert, steer,and/or otherwise control a flow of current through, for example, thestimulation circuit 249 to selectively provide at least a portion of theflow of current to the electrode assembly 220.

In some embodiments, the electrode assembly 220 can include one or moreelectrodes in electrical communication with a portion of theneuromuscular system that is associated with eversion or inversion ofthe foot. In such embodiments, a sensor (e.g., the sensor 230) can senseand/or determine a characteristic associated with eversion or inversionof the foot of an impaired leg and can send a signal associated with thecharacteristic to the electric stimulator 240. In this manner, theprocessor 247 can be configured to perform or execute one or morefunctions, processes, modules, and/or the like that is associated withdirecting, diverting, and/or otherwise controlling a flow of currentthrough the stimulation circuit 249 such that a desired amount of FES isprovided to the portion of the neuromuscular system controlling eversionand inversion (e.g., superficial portions of the peroneal nerve and/orthe like).

In some embodiments, the electrode assembly 220 can include a set ofelectrodes, with each electrode being in electrical communication with adifferent portion of the neuromuscular system. Moreover, the electrodeassembly 220 can be electrically coupled to the electric stimulator 240such that each electrode is in electrical connection with a differentelectric communication channel of the electric stimulator 240. In thismanner, the set of electrodes can define and/or bound an area ofstimulation to be applied to, for example, an impaired limb. Asdescribed above, the processor 247 can be configured to execute a set ofinstructions (e.g., stored in the memory 246) associated with increasingor decreasing a voltage provided to each electrode in a substantiallyconcurrent process based at least in part on a signal received from thesensor 230 (or multiple sensors). Thus, the electric stimulator 240 candirect, steer, divert, and/or otherwise control (i.e., increase ordecrease) a voltage provided to the set of electrodes to continuouslycontrol (e.g., during gate) an amount of dorsiflexion, plantarflexion,eversion, inversion, and/or the like to, for example, increase astability of the impaired limb and/or the patient during gait.

As shown in FIG. 8, in some embodiments, the electric stimulator 240 canbe in communication with one or more control devices 260 and 260′. Thecontrol device 260 can be any suitable electronic device that canprovide an interface for a user (e.g., the patient and/or a health careprofessional) to manipulate one or more characteristics and/orparameters associated with the FES. For example, in some embodiments,the control device 260 can be, for example, a smart phone or the likethat can be manipulated to run and/or execute a set of instructionsassociated with controlling the electric stimulator 240. Similarly, thecontrol device 260′ can be a personal computer (PC), a laptop, a tabletPC, a server device, a workstation, and/or the like that can bemanipulated to run and/or execute a set of instructions associated withcontrolling the electric stimulator 240. In some instances, the controldevice 260 can be in communication with the electric stimulator 240 viathe communication device 248. Although shown in FIG. 8 as being incommunication with one or more control devices, in other embodiments,the electric stimulator 240 can include any suitable hardware and/orsoftware that can, for example, enable to the electric stimulator tofunction as a control device. For example, in some embodiments, theelectric stimulator 240 can include a user interface and/or the likethat can be manipulated by a user to control at least a portion of theelectric stimulator 240.

In some instances, the electric stimulator 240 can be configured tocommunication with any number of electronic devices. For example, insome embodiments, the electric stimulator 240 can be in electricalcommunication with the control devices 260 and 260′, a physicallydistinct sensor 230, and an electric stimulator 240′ of a secondorthosis 205′. In such embodiments, the electric stimulator 240 and/orthe communication device 248 can be configured to communicate with theelectronic devices via, for example, unique communication channels.Thus, the control devices 260 and 260′, the physically distinct sensor230, and the orthosis 205 and 205′ can collectively provide FES to apatient that can, for example, enhance the patient's gait or the like.More specifically, in some embodiments, the orthosis 205′ can beconfigured to be disposed, for example, about the thigh of the patientdonning the orthosis 205 (i.e., the thigh of the impaired leg). Theelectrodes (not shown) of the orthosis 205′ can be, for example, inelectrical communication with one or more portions of the neuromuscularsystem associated with, for example, the hamstring and/or thequadriceps. In some embodiments, the orthosis 205′ can be substantiallysimilar to or the same as the devices described in U.S. patentapplication Ser. No. 13/022,149 entitled, “Adjustable Orthosis forElectrical Stimulation of a Limb,” filed Feb. 7, 2011, the disclosure ofwhich is incorporated herein by reference in its entirety. Thus, theelectric stimulator 240 can be configured to communicate with theelectric stimulator 240′ to provide FES to substantially the entirety ofan impaired limb of the patient. Moreover, in some embodiments, theelectronic stimulator 240′ can be substantially similar to or the sameas the electric stimulator 240 and as such, can be in direct electriccommunication with the sensor 230′ (e.g., via a wired or wirelessconnection). In other words, the sensor 230′ can be configured to send asignal associated with a gait event to the electric stimulator 240 ofthe orthosis 205 and the electric stimulator 240′ of the orthosis 205.

In some embodiments, the electric stimulator 240 can be in electricalcommunication with, for example, an electric stimulator 240″ of anorthosis 205″ disposed about a portion of a contralateral leg, as shownin FIG. 8. For example, in some instances, a patient can have a physicalimpairment of both legs (either equally impaired or one leg having agreater level of impairment). In such instances, the patient can don theorthosis 205 on a first leg (as described above) and can don theorthosis 205″ on a second leg (i.e., the contralateral leg). Thus, theelectric stimulator 240 of the orthosis 205 and the electric stimulator240″ of the orthosis 205″ can be configured to communicate with eachother, with the sensor 230′, the control devices 260 and/or 260′, and/orthe electric stimulator 240′ orthosis 205′. Although not shown in FIG.8, in some embodiments, the electric stimulator 240 can be in electricalcommunication with an FES orthosis in electrical communication with anysuitable portion of the neuromuscular system of the patient. Forexample, in some embodiments, the electric stimulator 240 of theorthosis 205 can be in electrical communication with an electricstimulator of an orthosis disposed about a portion of an impaired armand/or the like.

FIG. 9 is a flowchart illustrating a method 1000 of using an FESorthosis for gait modulation according to an embodiment. The FESorthosis can be any suitable neuroprosthetic and/or the like such as theorthosis 100 and/or 200 described herein. As such, the orthosis caninclude a frame, an electrode assembly, a sensor, and an electricstimulator, and can be coupled to and/or disposed about an impaired legof a patient to provide FES thereto. The method 1000 includes receiving,at the electric stimulator and from the sensor, a first signalassociated with a gait characteristic, at 1001. For example, in someembodiments, the electric stimulator can be substantially similar inform and function as the electric stimulator 240 described above withreference to FIG. 7. Similarly, the sensor can be substantially similarin form and function as the sensor 230 described above with reference toFIG. 7. In this manner, the sensor can include one or more sensingdevices such as, for example, a tilt sensor, pressure sensor,accelerometer, gyroscope, etc. that can sense and/or detect the gaitcharacteristic. In some embodiments, the gait characteristic can beassociated with, for example, a “heel-off” event or the like of theimpaired leg (e.g., a decrease in pressure as a result of the heel beinglifted away from a surface upon which the patient is walking and/or anyother suitable characteristic). As such, the sensor can sense and/ordetect the gait characteristic and can send the first signal to theelectric stimulator. As described above, in some embodiments, the sensorcan be integrated with the electric stimulator and as such, the firstsignal can be sent via a communication channel associated with a wiredsignal transmission (e.g., along a wire and/or a signal trace). In otherembodiments, the sensor can be physically distinct from the electricstimulator, and as such, the first signal can be sent via acommunication channel associated with a wireless signal transmission(e.g., WiFi®, Bluetooth®, etc.).

Upon receipt, one or more system parameters are calculated based atleast in part on the first signal associated with the gaitcharacteristic, at 1002. For example, in some embodiments, the electricstimulator can include at least a memory and a processor. The memory canstore instructions to cause the processor to perform and/or execute oneor more functions, processes, modules, and/or the like associated withcalculating the one or more system parameters. As such, the processorcan receive the first signal from the sensor and can calculate and/orotherwise determine the one or more system parameters associated withthat gait characteristic. By way of example, in some embodiments, thememory can include and/or can store a repository that includes a list ofgait characteristics and a list of processes and/or functions to beexecuted by the processor that are associated therewith. In suchembodiments, the processor can, for example, query the repository todetermine the one or more system parameters associated with the firstsignal received from the sensor. In other embodiments, the electricstimulator can be in communication with a control device or the like(e.g., via a wired or wireless connection) that can include and/or storethe repository. For example, in some embodiments, the control device canbe substantially similar to the control device 260 described above withreference to FIG. 8.

Based at least in part on the one or more system parameters, a signal issent from the electric stimulator to the electrode assembly to cause theelectrode assembly to provide an electric stimulation to a portion ofthe neuromuscular system of the limb, at 1003. For example, in someembodiments, the FES orthosis can be disposed about and/or can at leastpartially envelop a portion of the impaired leg to substantially alignand/or otherwise place one or more electrodes in electricalcommunication with, for example, the peroneal nerve of the impaired leg.Thus, electric stimulation is provided to a set of muscles associatedwith the portion of the neuromuscular system of the impaired leg,resulting in dorsiflexion of the foot of the impaired leg (i.e., apivoting of the foot substantially about the ankle towards the leg).

The method 1000 includes receiving, at the electric stimulator and fromthe sensor, a second signal associated with the gait characteristic, at1004. For example, in some embodiments, the gait characteristic can beassociated with a “heel-on” event or the like of the impaired leg (e.g.,an increase in pressure as a result of the heel being placed in contactwith the surface and/or any other suitable characteristic). As such, thesensor can sense and/or detect the gait characteristic and can send thesecond signal to the electric stimulator.

Based on receiving the second signal associated with the gaitcharacteristic, the electric stimulation of the portion of theneuromuscular system of the limb is terminated, at 1005. For example, insome embodiments, the electric stimulator can be configured to open anelectrical circuit between a power supply (e.g., that generates theelectric current for stimulation) and the electrode assembly. In otherembodiments, the electric stimulator can transition the power supply orthe like from an “on” state, in which electrical current is transmittedto the electrode assembly, to an “off” state or the like (e.g., sleep,hibernate, standby, etc.), in which electrical current is nottransmitted to the electrode assembly. In still other embodiments, theelectric stimulator can modulate an amount of stimulation (e.g., avoltage of the current provided to the electrode assembly) from a firstamount resulting in, for example, the dorsiflexion of the limb to asecond amount resulting in a substantially relaxing of the portion ofthe neuromuscular system. Said another way, the electric stimulator canmodulate stimulation such that an intensity of the stimulation providedto the portion of the neuromuscular system of the limb is reduced (i.e.,the electric stimulator does not substantially terminate the stimulationbut reduces the amount of stimulation to a minimal setting and/or thelike). As a result, the electric stimulation applied to, for example,the peroneal nerve is terminated and/or modulated, thereby allowing theset of muscles associated therewith to relax. Thus, the foot of theimpaired leg can pivot about the ankle away from the leg (i.e.,plantarflexion). In this manner, the FES orthosis can provide functionalelectrical stimulation that can enhance the function of the impaired legto facilitate gait.

Although the method 1000 described above includes the electricstimulator receiving a first signal and a second signal from the sensor,in some instances, the sensor can be configured to send any number ofsignals to the electric stimulator that can be, for example, associatedwith adjusting one or more parameters of the electric stimulationprovided to the neuromuscular system of the limb. By way of example, insome instances, the sensor can send the signal to the electricstimulator (i.e., at 1003) and can be configured to sense and/orotherwise detect an amount of the dorsiflexion and/or inversion oreversion of the foot in response to the electric stimulation and basedon the sensed and/or detected characteristic, can send one or moresignals to the electric stimulator (i.e., prior to the signal sent at1004) associated with adjusting one or more parameters of the electricstimulation (e.g., a voltage provided to one or more portions of theelectrode assembly and/or the like).

Although the method 1000 described above includes the electricstimulator terminating and/or modulating the electric stimulation basedon receiving the second signal from the sensor, in some instances, theelectric stimulator can terminate and/or modulate the electricstimulation based on any set of signals, parameters, history, and/or thelike. For example, in some instances, the electric stimulator canreceive the second signal from the sensor and can compare data includedin and/or represented by the second signal with historical data such as,for example, a previous gait event and/or the like. As such, theelectric stimulator can be configured to adjust, terminate, and/ormodulate the electric stimulation provided to the portion of theneuromuscular based at least in part on the second signal and/or anyother data associated with a gate event, characteristic, and/orparameter.

FIG. 10 is a flowchart illustrating a method 1100 of using an FESorthosis for gait modulation according to an embodiment. The FESorthosis can be any suitable neuroprosthetic and/or the like such as theorthosis 100 and/or 200 described herein. As such, the orthosis caninclude a frame, an electrode assembly, a sensor, and an electricstimulator, and can be coupled to and/or disposed about an impaired legof a patient to provide FES thereto. The method 1100 includes receiving,at the electric stimulator and from a control device, a first signalthat is associated with a system parameter via a first communicationchannel, at 1101. The control device can be any suitable device such as,for example, the control devices 160, 260, and/or 260′ described herein.The first communication channel can be associated with a wirelesscommunication over a network. For example, the electric stimulator caninclude a communication device such as the communication device 248 inFIG. 7, which can communicate with one or more electronic devices. Thenetwork and the communication channel can be any suitable network andcommunication channel, respectively, such as those described herein. Byway of example, in some embodiments, the network can be a personal areanetwork (PAN) and the communication channel can be associated withBluetooth®.

In some embodiments, the system parameter can be associated with, forexample, an initialization of the FES orthosis. For example, in someembodiments, the patient can be receiving FES therapy for the first timeand as such, system parameters and/or settings of the FES orthosis maynot be appropriately defined for the patient. As such, a health careprovider can manipulate the control device (e.g., a smart phone, a PC, atablet, etc.) to define an initial set of system characteristics and/ora second of calibration parameters for the FES orthosis that areuniquely established for the patient. In some instances, with the firstcommunication channel being associated with a wireless communicationover a network, a health care professional can manipulate the controldevice to define the system parameter substantially remotely (e.g., at alocation physically distinct from the FES orthosis). By way of example,the health care professional can be at a medical facility and canmanipulate the control device to define the system parameter and cansend the first signal via, for example, a LAN and the Internet to theFES orthosis worn by a patient that is at his or her home (or any otherlocation other than the medical facility). Upon receipt of the firstsignal, a second signal that is associated with a confirmation of thesystem parameter is sent from the electric stimulator to the controldevice, at 1102. In some embodiments, the second signal can be sent in asimilar manner as described with reference to the first signal.

The electric stimulator receives a third signal that is from the sensorvia a second communication channel, different from the firstcommunication channel, at 1103. The sensor can be substantially similarin form and function as the sensor 230 described above with reference toFIG. 7. In this manner, the sensor can include one or more sensingdevices such as, for example, a tilt sensor, pressure sensor,accelerometer, gyroscope, etc. that can sense and/or detect the gaitcharacteristic. In some embodiments, the gait characteristic can beassociated with, for example, a “heel-off” event or the like of theimpaired leg (e.g., a decrease in pressure as a result of the heel beinglifted away from a surface upon which the patient is walking and/or anyother suitable characteristic). In other embodiments, the gaitcharacteristic can be associated with any suitable gait event.

Based at least in part on the system parameter and the gaitcharacteristic, a fourth signal is sent, from the electric stimulator tothe electrode assembly, to cause the electrode assembly to provide anelectric stimulation to a portion of a neuromuscular system of the limb(e.g., the impaired leg), at 1104. For example, in some embodiments, theFES orthosis can be disposed about and/or can at least partially envelopa portion of the impaired leg to substantially align and/or otherwiseplace one or more electrodes included in the electrode assembly inelectrical communication with, for example, the peroneal nerve of theimpaired leg. Thus, electric stimulation is provided to a set of musclesassociated with the portion of the neuromuscular system of the impairedleg, resulting in dorsiflexion of the foot of the impaired leg (i.e., apivoting of the foot substantially about the ankle towards the leg).Thus, the FES orthosis can be used to enhance limb function of theimpaired leg to mitigate the effects of, for example, lower legparalysis such as drop foot or the like.

Although the embodiments and methods have been described above asproviding functional electrical stimulation to an impaired leg of apatient experiencing, for example, drop foot, in other embodiments, theembodiments and methods can be used to enhance the function of anysuitable limb or other portion of the body. By way of example, in someembodiments, an FES orthosis can include a frame, an electrode assembly,a sensor, and an electric stimulator and can be adapted to enhance thefunction of a patients hand or the like. In some instances, the sensorof such FES orthosis can be configured to sense and/or detect one ormore characteristics associated with the function of the hand and cansend a signal to the electric stimulator (in a similar manner asdescribed above) that is associated with the one or morecharacteristics. As such, the electric stimulator can generate anelectrical current that can be transmitted through one or moreelectrodes included in the electrode assembly, thereby providing FES toone or more nerves associated with the function of the hand.

While the embodiments and methods have been described above as includingan electrode assembly that is physically coupled to an FES orthosis andthat is disposed adjacent to an external surface of the body of apatient, in other embodiments, an FES orthosis can include and/or canotherwise be coupled to an electrode assembly that can be at leastpartially disposed within a portion of the body of the patient. Forexample, in some embodiments, an FES orthosis can be operably coupled toan electrode assembly that includes electrodes disposed within the bodyof a patient. In some embodiments, at least a portion of the electrodeassembly can be disposed within the body in such a manner that theelectrodes are disposed adjacent to and/or in electrical communicationwith, for example, the peroneal nerve, the tibial nerve, and/or anyother suitable portion of a neuromuscular system of the patient. In someembodiments, the electrode assembly can include one or more externalconnectors configured to place the electrodes disposed within the bodyin electrical communication with an electric device that is disposedexternally of the body. In other embodiments, the electrode assemblyneed not include such connectors and can transmit a flow of electricalcurrent via, for example, inductive coupling and/or the like.

Although the embodiments and methods have been described above asincluding a sensor that can be integrate into an FES orthosis and/orthat can be coupled to a structure substantially outside of the body(e.g., a shoe, the orthosis, etc.), in other embodiments, an FESorthosis can include and/or can otherwise be in communication with oneor more sensors disposed within the body of a patient. For example, insome embodiments, a relatively small sensor can be subcutaneouslyimplanted into a portion of the patient's foot, ankle, lower leg, upperleg, and/or any other suitable portion of the body.

While various embodiments have been described above, it should beunderstood that they have been presented by way of example only, and notlimitation. Where schematics and/or embodiments described above indicatecertain components arranged in certain orientations or positions, thearrangement of components may be modified. While the embodiments havebeen particularly shown and described, it will be understood thatvarious changes in form and details may be made. Although variousembodiments have been described as having particular features and/orcombinations of components, other embodiments are possible having acombination of any features and/or components from any of embodiments asdiscussed above.

Where methods and/or events described above indicate certain eventsand/or procedures occurring in certain order, the ordering of certainevents and/or procedures may be modified. Additionally, certain of theevents may be performed concurrently in a parallel process whenpossible, as well as performed sequentially as described above.

Some embodiments described herein relate to a computer storage productwith a non-transitory computer-readable medium (also can be referred toas a non-transitory processor-readable medium) having instructions orcomputer code thereon for performing various computer-implementedoperations. The computer-readable medium (or processor-readable medium)is non-transitory in the sense that it does not include transitorypropagating signals per se (e.g., a propagating electromagnetic wavecarrying information on a transmission medium such as space or a cable).The media and computer code (also can be referred to as code) may bethose designed and constructed for the specific purpose or purposes.Examples of non-transitory computer-readable media include, but are notlimited to, magnetic storage media such as hard disks, floppy disks, andmagnetic tape; optical storage media such as Compact Disc/Digital VideoDiscs (CD/DVDs), Compact Disc-Read Only Memories (CD-ROMs), andholographic devices; magneto-optical storage media such as opticaldisks; carrier wave signal processing modules; and hardware devices thatare specially configured to store and execute program code, such asApplication-Specific Integrated Circuits (ASICs), Programmable LogicDevices (PLDs), Read-Only Memory (ROM) and Random-Access Memory (RAM)devices. Other embodiments described herein relate to a computer programproduct, which can include, for example, the instructions and/orcomputer code discussed herein.

Some embodiments and/or methods described herein can be performed bysoftware (executed on hardware), hardware, or a combination thereof.Hardware modules may include, for example, a general-purpose processor,a field programmable gate array (FPGA), and/or an application specificintegrated circuit (ASIC). Software modules (executed on hardware) canbe expressed in a variety of software languages (e.g., computer code),including C, C++, Java™, Ruby, Visual Basic™, and/or otherobject-oriented, procedural, or other programming language anddevelopment tools. Examples of computer code include, but are notlimited to, micro-code or micro-instructions, machine instructions, suchas produced by a compiler, code used to produce a web service, and filescontaining higher-level instructions that are executed by a computerusing an interpreter. Additional examples of computer code include, butare not limited to, control signals, encrypted code, and compressedcode.

What is claimed is:
 1. An apparatus, comprising: a frame assemblyconfigured to be removably coupled to a portion of a limb such that theportion of the limb is substantially enveloped by the frame; a sensorcoupled to the frame, the sensor including one of a tilt sensor, anaccelerometer or a gyroscope, the sensor configured to produce a firstsignal and a second signal, the first signal associated with a gaitcharacteristic at a first time, the second signal associated with thegait characteristic at a second time, after the first time, the firsttime and the second time defining a time period therebetween; and anelectric stimulator removably coupled to the frame assembly and inelectrical communication with the sensor and an electrode assembly, theelectrode assembly including a first set of electrodes configured to bein electrical communication with a first portion of a neuromuscularsystem of the limb, the electrode assembly including a second set ofelectrodes configured to be in electrical communication with a secondportion of the neuromuscular system of the limb, the electric stimulatorconfigured to receive the first signal from the sensor at the first timeand the second signal from the sensor at the second time; the electricstimulator configured to send a third signal to the electrode assemblyat the first time, the third signal based at least in part on the firstsignal associated with the gait characteristic at the first time, thethird signal operable to cause the first set of electrodes of theelectrode assembly to provide an electrical stimulation having a firstvoltage to the first portion of the neuromuscular system of the limbresulting in dorsiflexion of a foot of the limb and to cause the secondset of electrodes of the electrode assembly to provide an electricalstimulation having a second voltage, different from the first voltage,to the second portion of the neuromuscular system during the time periodresulting in plantarflexion of the foot of the limb.
 2. The apparatus ofclaim 1, wherein the gait characteristic is at least one of a tiltcharacteristic, an acceleration characteristic, or an angularcharacteristic.
 3. The apparatus of claim 1, wherein the first signal atthe first time is associated with a heel-off event and the second signalat the second time is associated with a heel-on event.
 4. The apparatusof claim 1, wherein at least a portion of the electric stimulator isdisposed in a housing and at least a portion of the sensor is disposedin the housing.
 5. The apparatus of claim 1, wherein the sensor is afirst sensor, the gait characteristic is a first gait characteristic,the first signal and the second signal being received by the electricstimulator via a first communication channel, the apparatus furthercomprising: a second sensor physically distinct from the electricstimulator, the second sensor configured to produce a fourth signal anda fifth signal, the fourth signal associated with a second gaitcharacteristic at the first time, the second signal associated with thesecond gait characteristic at the second time; and the electricstimulator configured to receive the fourth signal from the secondsensor substantially at the first time and the fifth signal from thesecond sensor substantially at the second time, the fourth signal andthe fifth signal being received by the electric stimulator via a secondcommunication channel, different from the first communication channel,the third signal sent from the electric stimulator based at least inpart on the first gait characteristic and the second gaitcharacteristic.
 6. The apparatus of claim 5, wherein the second sensoris coupled to at least one of a shoe, a sock, a band, or an adhesivedisposed about a foot of the limb.
 7. The apparatus of claim 1, whereinthe first signal and the second signal are received by the electricstimulator via a first communication channel, the electric stimulator isin wireless electrical communication with a control device via a secondcommunication channel, different from the first communication channel,the control device configured to send a fourth signal to the electricstimulator, the fourth signal associated with one or more systemparameters.
 8. The apparatus of claim 1, wherein the electric stimulatoris configured to electrically communicate via three communicationchannels.
 9. The apparatus of claim 1, wherein the stimulator isconfigured to, based on at least one of the first signal or the secondsignal produced by the sensor, reduce the first voltage and increase thesecond voltage.
 10. The apparatus of claim 1, wherein the electricstimulator is configured to electrically communicate via a plurality ofcommunication channels, at least a first communication channel from theplurality of communication channels associated with a wired signaltransmission, at least a second communication channel from the pluralityof communication channels, different from the first communicationchannel, associated with a wireless signal transmission.
 11. Theapparatus of claim 1, wherein the sensor is at least partially includedin the electric stimulator.
 12. The apparatus of claim 1, wherein thelimb is a first limb, the sensor is a first sensor, the communicationchannel is a first communication channel, the apparatus furthercomprising: a second sensor physically distinct from the electricalstimulator and associated with a segment of a second limb, the secondlimb being contralateral to the first limb, the second sensor configuredto produce a fourth signal, the electric stimulator configured toreceive the fourth signal from the second sensor via a secondcommunication channel, different from the first communication channel.13. An apparatus, comprising: a frame assembly configured to beremovably coupled to a portion of a first limb such that the portion ofthe first limb is substantially enveloped by the frame assembly; anelectric stimulator removably coupled to the frame assembly and inelectrical communication with the electrode assembly, the electrodeassembly configured to be in electrical communication with a portion ofa neuromuscular system of the first limb; and a sensor physicallydistinct from and in wireless electrical communication with the electricstimulator, the sensor being associated with a second limb contralateralto the first limb, the sensor configured to produce a first signal and asecond signal, the first signal associated with a gait characteristic ata first time, the second signal associated with the gait characteristicat a second time, after the first time, the first time and the secondtime defining a time period therebetween; the electric stimulatorconfigured to receive the first signal from the sensor at the first timeand the second signal from the sensor at the second time, the electricstimulator configured to send a third signal to the electrode assemblyat the first time, the third signal based at least in part on the firstsignal and operable to cause the electrode assembly to provide anelectrical stimulation to the portion of the neuromuscular system of thefirst limb during the time period resulting in at least one ofdorsiflexion or plantarflexion of a foot of the first limb.
 14. Theapparatus of claim 13, wherein the sensor includes at least one of anaccelerometer and a gyroscope.
 15. The apparatus of claim 13, whereinthe gait characteristic is at least one of an accelerationcharacteristic or a stabilization characteristic.
 16. The apparatus ofclaim 13, wherein the electric stimulation during the time periodtransmitted to the portion of the neuromuscular system of the first limbhas a first voltage during a first portion of the time period and asecond voltage, less than the first voltage, during a second portion ofthe time period subsequent the first portion of the time period.
 17. Theapparatus of claim 13, wherein the first signal at the first time isassociated with a heel-off event and the second signal at the secondtime is associated with a heel-on event.
 18. The apparatus of claim 13,wherein the sensor is a first sensor, the gait characteristic is a firstgait characteristic, the first signal and the second signal beingreceived by the electric stimulator via a first wireless communicationchannel, the apparatus further comprising: a second sensor coupled tothe frame, the second sensor configured to produce a fourth signal and afifth signal, the fourth signal associated with a second gaitcharacteristic at the first time, the second signal associated with thesecond gait characteristic at the second time; and the electricstimulator configured to receive the fourth signal from the secondsensor at the first time and the fifth signal from the second sensor atthe second time, the fourth signal and the fifth signal being receivedby the electric stimulator via one of a wired communication channel or asecond wireless communication channel, different from the first wirelesscommunication channel, the third signal sent from the electricstimulator based at least in part on the first gait characteristic andthe second gait characteristic.
 19. The apparatus of claim 13, whereinthe electric stimulator is configured to electrically communicate viathree communication channels.
 20. The apparatus of claim 13, wherein theelectric stimulator is a first electric stimulator, further comprising:a second electric stimulator associated with the second limb and inelectrical communication with the sensor.
 21. The apparatus of claim 1,wherein the electric stimulator is configured to cause the electricalstimulation to the portion of the neuromuscular system of the limb tocease based at least in part on the second signal received from thesensor at the second time.
 22. The apparatus of claim 1, wherein: theelectric stimulator is configured to send a fourth signal to theelectrode assembly at the second time, the fourth signal based at leastin part on the gait characteristic at the second time and operable tocause the electrode assembly to cease providing the electricalstimulation to the portion of the neuromuscular system of the limbresulting in dorsiflexion of the foot of the limb and to increase thesecond voltage of the electrical stimulation to the portion of theneuromuscular system of the limb resulting in plantarflexion of the footof the limb.
 23. An apparatus, comprising: a frame assembly configuredto be removably coupled to a portion of a limb such that the portion ofthe limb is substantially enveloped by the frame; a first sensor coupledto the frame, the sensor including at least one of a tilt sensor, anaccelerometer or a gyroscope, the first sensor configured to produce afirst signal and a second signal, the first signal associated with afirst gait characteristic at a first time, the second signal associatedwith the first gait characteristic at a second time, after the firsttime, the first time and the second time defining a time periodtherebetween; a second sensor configured to produce a third signal and afourth signal, the third signal associated with a second gaitcharacteristic at the first time, the fourth signal associated with thesecond gait characteristic at the second time; and an electricstimulator removably coupled to the frame assembly and in electricalcommunication with the first sensor, the second sensor and an electrodeassembly, the second sensor being physically distinct from the electricstimulator, the electrode assembly configured to be in electricalcommunication with a portion of a neuromuscular system of the limb, theelectric stimulator configured to receive, at the first time, the firstsignal from the first sensor and the third signal from the secondsensor, the electric stimulator configured to receive, at the secondtime, the second signal from the first sensor and the fourth signal fromthe second sensor; the electric stimulator configured to send a fifthsignal to the electrode assembly at the first time, the fifth signalbased at least in part on the first gait characteristic at the firsttime and the second gait characteristic at the first time, the fifthsignal operable to cause the electrode assembly to provide an electricalstimulation to the portion of the neuromuscular system of the limbduring the time period such that the electrical stimulation has a firstvoltage during a first portion of the time period and a second voltage,different than the first voltage, during a second portion of the timeperiod subsequent the first portion of the time period.